sink(ticdc): Add csv decoder into codec

cdc/sink/codec/csv/csv_decoder.go

@@ -0,0 +1,99 @@
+// Copyright 2022 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package csv
+
+import (
+	"context"
+
+	"github.com/pingcap/errors"
+	lconfig "github.com/pingcap/tidb/br/pkg/lightning/config"
+	"github.com/pingcap/tidb/br/pkg/lightning/mydump"
+	"github.com/pingcap/tidb/br/pkg/lightning/worker"
+	"github.com/pingcap/tiflow/cdc/model"
+	"github.com/pingcap/tiflow/cdc/sink/codec"
+	"github.com/pingcap/tiflow/pkg/config"
+	cerror "github.com/pingcap/tiflow/pkg/errors"
+)
+
+type batchDecoder struct {
+	csvConfig *config.CSVConfig
+	parser    *mydump.CSVParser
+	data      []byte
+	msg       *csvMessage
+	closed    bool
+}
+
+// NewBatchDecoder creates a new BatchDecoder
+func NewBatchDecoder(ctx context.Context, csvConfig *config.CSVConfig, value []byte) (codec.EventBatchDecoder, error) {
+	var backslashEscape bool
+
+	if len(csvConfig.Quote) == 0 {
+		backslashEscape = true
+	}
+	cfg := &lconfig.CSVConfig{
+		Separator:       csvConfig.Delimiter,
+		Delimiter:       csvConfig.Quote,
+		Terminator:      csvConfig.Terminator,
+		Null:            csvConfig.NullString,
+		BackslashEscape: backslashEscape,
+	}
+	csvParser, err := mydump.NewCSVParser(ctx, cfg,
+		mydump.NewStringReader(string(value)),
+		int64(lconfig.ReadBlockSize),
+		worker.NewPool(ctx, 1, "io"), false, nil)
+	if err != nil {
+		return nil, err
+	}
+	return &batchDecoder{
+		csvConfig: csvConfig,
+		data:      value,
+		parser:    csvParser,
+	}, nil
+}
+
+// HasNext implements the EventBatchDecoder interface.
+func (b *batchDecoder) HasNext() (model.MessageType, bool, error) {
+	err := b.parser.ReadRow()
+	if err != nil {
+		b.closed = true
+		return model.MessageTypeUnknown, false, err
+	}
+
+	row := b.parser.LastRow()
+	csvMsg := newCSVMessage(b.csvConfig)
+	if err = csvMsg.decode(row.Row); err != nil {
+		return model.MessageTypeUnknown, false, errors.Trace(err)
+	}
+	b.msg = csvMsg
+
+	return model.MessageTypeRow, true, nil
+}
+
+// NextResolvedEvent implements the EventBatchDecoder interface.
+func (b *batchDecoder) NextResolvedEvent() (uint64, error) {
+	return 0, nil
+}
+
+// NextRowChangedEvent implements the EventBatchDecoder interface.
+func (b *batchDecoder) NextRowChangedEvent() (*model.RowChangedEvent, error) {
+	if b.closed {
+		return nil, cerror.WrapError(cerror.ErrCSVDecodeFailed, errors.New("no csv row can be found"))
+	}
+	return csvMsg2RowChangedEvent(b.msg), nil
+}
+
+// NextDDLEVent implements the EventBatchDecoder interface.
+func (b *batchDecoder) NextDDLEvent() (*model.DDLEvent, error) {
+	return nil, nil
+}

cdc/sink/codec/csv/csv_decoder_test.go

@@ -0,0 +1,53 @@
+// Copyright 2022 PingCAP, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//	http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package csv
+
+import (
+	"context"
+	"testing"
+
+	"github.com/pingcap/tiflow/cdc/model"
+	"github.com/pingcap/tiflow/pkg/config"
+	"github.com/stretchr/testify/require"
+)
+
+func TestCSVBatchDecoder(t *testing.T) {
+	csvData := `"I","employee","hr",433305438660591626,101,"Smith","Bob","2014-06-04","New York"
+"U","employee","hr",433305438660591627,101,"Smith","Bob","2015-10-08","Los Angeles"
+"D","employee","hr",433305438660591629,101,"Smith","Bob","2017-03-13","Dallas"
+"I","employee","hr",433305438660591630,102,"Alex","Alice","2017-03-14","Shanghai"
+"U","employee","hr",433305438660591630,102,"Alex","Alice","2018-06-15","Beijing"
+`
+	ctx := context.Background()
+	decoder, err := NewBatchDecoder(ctx, &config.CSVConfig{
+		Delimiter:       ",",
+		Quote:           "\"",
+		Terminator:      "\n",
+		NullString:      "\\N",
+		IncludeCommitTs: true,
+	}, []byte(csvData))
+	require.Nil(t, err)
+
+	for i := 0; i < 5; i++ {
+		tp, hasNext, err := decoder.HasNext()
+		require.Nil(t, err)
+		require.True(t, hasNext)
+		require.Equal(t, model.MessageTypeRow, tp)
+		event, err := decoder.NextRowChangedEvent()
+		require.Nil(t, err)
+		require.NotNil(t, event)
+	}
+
+	_, hasNext, _ := decoder.HasNext()
+	require.False(t, hasNext)
+}

cdc/sink/codec/csv/csv_encoder.go

@@ -45,11 +45,11 @@ func (b *BatchEncoder) AppendRowChangedEvent(
 			errors.New("no csv config provided"))
 	}
 
-	row, err := buildRowData(b.csvConfig, e)
+	row, err := rowChangedEvent2CSVMsg(b.csvConfig, e)
 	if err != nil {
 		return err
 	}
-	b.valueBuf.Write(row)
+	b.valueBuf.Write(row.encode())
 	b.batchSize++
 	if callback != nil {
 		b.callbackBuf = append(b.callbackBuf, callback)